The present invention relates to an apparatus for the separation by filtration of a solid phase and a liquid phase from a sludge, slurry, or suspension, a method for separation by filtration which can be employed in the said apparatus, and the use of the said apparatus for the treatment of liquid manure. The generic term "sludge" will be used hereinbelow to denote any suspension or dispersion of a particulate solid phase in at least one liquid phase.